Prior art U.S. Pat. No. 1,441,146 issued Jan. 2, 1923 discloses a film leader in the known form of a protective backing paper for a filmstrip stored on a flanged film spool. The film leader comprises a main leader portion having a pair of parallel straight edges between which the main leader portion has a constant width, and an extreme end portion extending from the main leader portion and having a pair of similarly tapered (converging) edges between which the extreme end portion has a gradually reducing width that is smaller than the width of the main leader portion. The extreme end portion is significantly shorter than the main leader portion. A non-inclined weakened fold-line longitudinally extends from one of the tapered edges of the extreme end portion to the other tapered edge of the extreme end portion to thus form a forward-most non-inclined straight edge of the extreme end portion when approximately a forward-most half of the extreme end portion is folded, along the fold-line, onto the remaining half of the extreme end portion. This is illustrated in FIG. 1 of the drawings, designated as "PRIOR ART", in this application. In FIG. 1, there is shown the film leader 10, the main leader portion 12, the pair of parallel straight edges 14 and 16, the constant width 18, the extreme end portion 20, the two tapered edges 22 and 24, the gradually reducing width 26, the fold-line 28, the forward-most non-inclined straight edge 30, the forward-most half 32, the remaining half 34, and the flanged film spool 36. The forward-most half 32 of the extreme end portion 20 is depicted in solid lines before being folded, along the fold-line 28, onto the remaining half 34 of the extreme end portion and in broken lines when folded onto the remaining half 34 of the extreme end portion.
The known ADVANCED Photo System.TM. introduced several years ago, includes a film leader that is an integral longitudinal end portion of a filmstrip stored inside a film cartridge. The film leader has a forward-most straight edge which substantially is uniformly inclined from one of the parallel straight edges of the film leader to the other parallel straight edge of the film leader. This is illustrated in FIG. 2 of the drawings, designated as "PRIOR ART", in this application. In FIG. 2, there is shown the film leader 40, the forward-most straight edge 42, the pair of parallel straight edges 44 and 46, and the film cartridge 48.